Change detection from multitemporal Landsat TM and Landsat ETM+ images was combined with fieldwor... more Change detection from multitemporal Landsat TM and Landsat ETM+ images was combined with fieldwork and GIS analysis to estimate the share of the illegally felled timber in Estonia for the period ranging from 1999 to 2002. A sample of changed areas (667) was selected from digital change map for the field inspection and detailed analysis. Map layers were created to represent the extent of problems found in the field. Finally, the problem layers were intersected to discriminate between different rule violation combinations and analyse their overlapping. A regression function was developed on the National Forest Inventory data for wood volume estimation. The results showed that for 9.4% of the felling areas the forest management declaration (FMD) was not submitted. 10.3% of the felled timber volume was related at least to one violation of forest felling regulations and 6.3% of the felled timber was connected to the environmental damages and unsustainable forest management. Rather high s...
Environmental Science and Pollution Research, 2015
Afforestation on reclaimed mining areas has high ecological and economic importance. However, eco... more Afforestation on reclaimed mining areas has high ecological and economic importance. However, ecosystems established on post-mining substrate can become vulnerable due to climate variability. We used tree-ring data and dendrochronological techniques to study the relationship between climate variables and annual growth of Scots pine (Pinus sylvestris L.) growing on reclaimed open cast oil shale mining areas in Northeast Estonia. Chronologies for trees of different age classes (50, 40, 30) were developed. Pearson's correlation analysis between radial growth indices and monthly climate variables revealed that precipitation in June-July and higher mean temperatures in spring season enhanced radial growth of pine plantations, while higher than average temperatures in summer months inhibited wood production. Sensitivity of radial increment to climatic factors on post-mining soils was not homogenous among the studied populations. Older trees growing on more developed soils were more sensitive to precipitation deficit in summer, while growth indices of two other stand groups (young and middle-aged) were highly correlated to temperature. High mean temperatures in August were negatively related to annual wood production in all trees, while trees in the youngest stands benefited from warmer temperatures in January. As a response to thinning, mean annual basal area increment increased up to 50 %. By managing tree competition in the closed-canopy stands, through the thinning activities, tree sensitivity and response to climate could be manipulated.
The method used in the Estonian Forest Conservation Area Network (EFCAN) project for inventorying... more The method used in the Estonian Forest Conservation Area Network (EFCAN) project for inventorying natural values (INV) was analyzed in order to explore its efficiency. The method has been extensively used for creating the EFCAN and describing the naturalness of forest stands and key habitats on the existing nature conservation areas and potential new conservation areas. For the purposes of comparison with commercial for-ests, another data set from INV in forests at Järvselja was used. The method is suitable for INV; however, it is dependent on forest site types. It works well in almost all fertile forest site types and relatively well in poor paludified and peatland forests. The method seems to not work in alvar and boreal heath forests and the Vaccinium vitis-idaea forest site type. The study showed that the method is virtually useless in distinguishing between potential key habitats and "real" key habitats as well as between recovering forests and commercial forests with...
Forest ownership in Estonia is in its youth – twenty years after the start of the restitution and... more Forest ownership in Estonia is in its youth – twenty years after the start of the restitution and privatization process roughly half of the forests are in private hands i.e. ~1 M ha. Although the first forest owners organizations emerged in the mid 90es the rate of cooperation is still rather slow – only 6% of forest owners (out of ~80,000) are members of Forest Owner Associations (FOA). The National Forestry Development Plan (NFDP) 2020 puts forward ambitious goals – 500,000 ha of private forests should be covered by owners with FOA memberships (baseline 150,000 ha) and during the 10 year period these forest owners should put 5 M m3 of wood on the market (baseline is 65,000 m3). The policy goals are quite straight forward, yet we argue that this kind of one-sided approach towards cooperation might not lead to desired results. Using datasets from FOA surveys conducted in 2007 and 2011 we aim to identify the main characteristics and differences between members who belong to FOA-s and...
Forest species, especially species habiting in old f orests, can be preserv ed by nature restorat... more Forest species, especially species habiting in old f orests, can be preserv ed by nature restoration activities in certain cases. Monitoring of restoration areas is a continuous long -term research, enabling to evaluate the success of restoration activities and, if necessary , to plan some additional ac tivities needed. Monitoring also enables to develop the methods of nature restoration. The main method for nature restoration monitoring is forest stand monitoring by permanent sample plots (PSP) , together with scoring of stand nature value and species-specific special inventories. Establishing of PSPs f or monitoring nature restoration areas was in 2001–2004. Restoration activities took plac e in 2005. 50 restoration areas with permanent sample plots were established. Re-measurements will be performed after restoration activities are completed.
We analysed tree stem size distributions in tree mapping data from a naturally developing forest ... more We analysed tree stem size distributions in tree mapping data from a naturally developing forest ecosystem - a primeval forest in Järvselja, Estonia (19.7 hectares). The primeval forest have been in natural successional development more than 90 years, before that very mild management activities have been carried out (occasional removal of dead trees). Tree and stand structure measurements were conducted in 2013, covering 8.78 hectares. We focus on the standing live and dead trees, laying trees and high snags in the study. The measurement in the stands include next to the tree locations description of the live and dead trees decay stages (5 decay classes), vitality (vital, poor, normal), dominance (co-dominant, subdominant etc.), tree layers, height (tree height, live crown base height and dead crown height) and diameter. Several earlier studies indicate that frequent disturbances in hemi-boreal forest result in a gradual change of species composition in favour of deciduous tree spec...
We examined the forest microhabitat rehabilitation on forest plantations established on the plane... more We examined the forest microhabitat rehabilitation on forest plantations established on the planed abandoned oil-shale mining sites in Northeast Estonia. For the rehabilitation purposes several native and exotic tree species were used in single species and mixed species trials established in 1968. On the test site due to the variation in local topography a variation in rehabilitation success can be observed. For describing the variation in microhabitat conditions we have estimated the topsoil depth with the so called re-bar method and described the topsoil structure with small characterization pits. The results indicate a strong correlation between the topsoil depth and the stone fraction proportion in topsoil.
The United Nations Climate Change Conference, Durban 2011, delivered a breakthrough on the intern... more The United Nations Climate Change Conference, Durban 2011, delivered a breakthrough on the international community’s response to climate change. In the second largest meeting of its kind, the negotiations advanced, in a balanced fashion, the implementation of the Convention and the Kyoto Protocol, the Bali Action Plan, and the Cancun Agreements. The outcomes included a decision by Parties to adopt a universal legal agreement on climate change as soon as possible, and no later than 2015. One of the decisions adopted by COP 17 and CMP 7 regard to the land use, landuse change and forestry, and invites the Intergovernmental Panel on Climate Change to review and, if necessary, update supplementary methodologies for estimating anthropogenic greenhouse gas emissions by sources and removals by sinks resulting from land use, land-use change and forestry activities under Article 3, paragraphs 3 and 4, of the Kyoto Protocol. Land degradation is a human-induced or natural process which negative...
The biodiversity considerations, development plans and progress of forest-conservation area netwo... more The biodiversity considerations, development plans and progress of forest-conservation area network in Estonia is analysed. In 1997 Estonian forest policy stated that 4% of the total forest area of Estonia should be strictly protected for maintaining the existing biodiversity. These areas are planned to choose, inventory and analyse during next few years and also establish geographical information system on the
Change detection from multitemporal Landsat TM and Landsat ETM+ images was combined with fieldwor... more Change detection from multitemporal Landsat TM and Landsat ETM+ images was combined with fieldwork and GIS analysis to estimate the share of the illegally felled timber in Estonia for the period ranging from 1999 to 2002. A sample of changed areas (667) was selected from digital change map for the field inspection and detailed analysis. Map layers were created to represent the extent of problems found in the field. Finally, the problem layers were intersected to discriminate between different rule violation combinations and analyse their overlapping. A regression function was developed on the National Forest Inventory data for wood volume estimation. The results showed that for 9.4% of the felling areas the forest management declaration (FMD) was not submitted. 10.3% of the felled timber volume was related at least to one violation of forest felling regulations and 6.3% of the felled timber was connected to the environmental damages and unsustainable forest management. Rather high s...
Environmental Science and Pollution Research, 2015
Afforestation on reclaimed mining areas has high ecological and economic importance. However, eco... more Afforestation on reclaimed mining areas has high ecological and economic importance. However, ecosystems established on post-mining substrate can become vulnerable due to climate variability. We used tree-ring data and dendrochronological techniques to study the relationship between climate variables and annual growth of Scots pine (Pinus sylvestris L.) growing on reclaimed open cast oil shale mining areas in Northeast Estonia. Chronologies for trees of different age classes (50, 40, 30) were developed. Pearson's correlation analysis between radial growth indices and monthly climate variables revealed that precipitation in June-July and higher mean temperatures in spring season enhanced radial growth of pine plantations, while higher than average temperatures in summer months inhibited wood production. Sensitivity of radial increment to climatic factors on post-mining soils was not homogenous among the studied populations. Older trees growing on more developed soils were more sensitive to precipitation deficit in summer, while growth indices of two other stand groups (young and middle-aged) were highly correlated to temperature. High mean temperatures in August were negatively related to annual wood production in all trees, while trees in the youngest stands benefited from warmer temperatures in January. As a response to thinning, mean annual basal area increment increased up to 50 %. By managing tree competition in the closed-canopy stands, through the thinning activities, tree sensitivity and response to climate could be manipulated.
The method used in the Estonian Forest Conservation Area Network (EFCAN) project for inventorying... more The method used in the Estonian Forest Conservation Area Network (EFCAN) project for inventorying natural values (INV) was analyzed in order to explore its efficiency. The method has been extensively used for creating the EFCAN and describing the naturalness of forest stands and key habitats on the existing nature conservation areas and potential new conservation areas. For the purposes of comparison with commercial for-ests, another data set from INV in forests at Järvselja was used. The method is suitable for INV; however, it is dependent on forest site types. It works well in almost all fertile forest site types and relatively well in poor paludified and peatland forests. The method seems to not work in alvar and boreal heath forests and the Vaccinium vitis-idaea forest site type. The study showed that the method is virtually useless in distinguishing between potential key habitats and "real" key habitats as well as between recovering forests and commercial forests with...
Forest ownership in Estonia is in its youth – twenty years after the start of the restitution and... more Forest ownership in Estonia is in its youth – twenty years after the start of the restitution and privatization process roughly half of the forests are in private hands i.e. ~1 M ha. Although the first forest owners organizations emerged in the mid 90es the rate of cooperation is still rather slow – only 6% of forest owners (out of ~80,000) are members of Forest Owner Associations (FOA). The National Forestry Development Plan (NFDP) 2020 puts forward ambitious goals – 500,000 ha of private forests should be covered by owners with FOA memberships (baseline 150,000 ha) and during the 10 year period these forest owners should put 5 M m3 of wood on the market (baseline is 65,000 m3). The policy goals are quite straight forward, yet we argue that this kind of one-sided approach towards cooperation might not lead to desired results. Using datasets from FOA surveys conducted in 2007 and 2011 we aim to identify the main characteristics and differences between members who belong to FOA-s and...
Forest species, especially species habiting in old f orests, can be preserv ed by nature restorat... more Forest species, especially species habiting in old f orests, can be preserv ed by nature restoration activities in certain cases. Monitoring of restoration areas is a continuous long -term research, enabling to evaluate the success of restoration activities and, if necessary , to plan some additional ac tivities needed. Monitoring also enables to develop the methods of nature restoration. The main method for nature restoration monitoring is forest stand monitoring by permanent sample plots (PSP) , together with scoring of stand nature value and species-specific special inventories. Establishing of PSPs f or monitoring nature restoration areas was in 2001–2004. Restoration activities took plac e in 2005. 50 restoration areas with permanent sample plots were established. Re-measurements will be performed after restoration activities are completed.
We analysed tree stem size distributions in tree mapping data from a naturally developing forest ... more We analysed tree stem size distributions in tree mapping data from a naturally developing forest ecosystem - a primeval forest in Järvselja, Estonia (19.7 hectares). The primeval forest have been in natural successional development more than 90 years, before that very mild management activities have been carried out (occasional removal of dead trees). Tree and stand structure measurements were conducted in 2013, covering 8.78 hectares. We focus on the standing live and dead trees, laying trees and high snags in the study. The measurement in the stands include next to the tree locations description of the live and dead trees decay stages (5 decay classes), vitality (vital, poor, normal), dominance (co-dominant, subdominant etc.), tree layers, height (tree height, live crown base height and dead crown height) and diameter. Several earlier studies indicate that frequent disturbances in hemi-boreal forest result in a gradual change of species composition in favour of deciduous tree spec...
We examined the forest microhabitat rehabilitation on forest plantations established on the plane... more We examined the forest microhabitat rehabilitation on forest plantations established on the planed abandoned oil-shale mining sites in Northeast Estonia. For the rehabilitation purposes several native and exotic tree species were used in single species and mixed species trials established in 1968. On the test site due to the variation in local topography a variation in rehabilitation success can be observed. For describing the variation in microhabitat conditions we have estimated the topsoil depth with the so called re-bar method and described the topsoil structure with small characterization pits. The results indicate a strong correlation between the topsoil depth and the stone fraction proportion in topsoil.
The United Nations Climate Change Conference, Durban 2011, delivered a breakthrough on the intern... more The United Nations Climate Change Conference, Durban 2011, delivered a breakthrough on the international community’s response to climate change. In the second largest meeting of its kind, the negotiations advanced, in a balanced fashion, the implementation of the Convention and the Kyoto Protocol, the Bali Action Plan, and the Cancun Agreements. The outcomes included a decision by Parties to adopt a universal legal agreement on climate change as soon as possible, and no later than 2015. One of the decisions adopted by COP 17 and CMP 7 regard to the land use, landuse change and forestry, and invites the Intergovernmental Panel on Climate Change to review and, if necessary, update supplementary methodologies for estimating anthropogenic greenhouse gas emissions by sources and removals by sinks resulting from land use, land-use change and forestry activities under Article 3, paragraphs 3 and 4, of the Kyoto Protocol. Land degradation is a human-induced or natural process which negative...
The biodiversity considerations, development plans and progress of forest-conservation area netwo... more The biodiversity considerations, development plans and progress of forest-conservation area network in Estonia is analysed. In 1997 Estonian forest policy stated that 4% of the total forest area of Estonia should be strictly protected for maintaining the existing biodiversity. These areas are planned to choose, inventory and analyse during next few years and also establish geographical information system on the
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